This invention relates to network interface units for telecommunications equipment.
A network interface unit is a terminal found in most buildings having several subscribers, and includes an array of bridges, each coupled to a subscriber in the building. Each bridge is also coupled to the telecommunications network through a standard RJ11 plug so that the subscriber can disconnect his premises equipment and plug a working phone directly into the network for testing purposes (see, e.g., U.S. Pat. No. 5,004,433, issued to Daoud). This apparatus permits the subscriber to determine if any problem lies in the network or with his or her own equipment or wiring.
A maintenance termination unit (MTU) also allows the phone company to determine where a service problem lies. The MTU permits the central office to electronically disconnect the customer equipment by transmitting a particular voltage signal and then determine if any communication problems are in the network or in the customer equipment (see e.g., U.S. Pat. No. 4,396,809 issued to Brunssen).
It is economically desirable to provide MTUs in the same terminal unit as the customer bridges. Typically, each MTU is formed on a printed circuit board with four wires extending therefrom for splicing onto the wires of the network side of the unit. Finding the right pairs of wires, and then cutting and splicing the wires for each MTU are time consuming and awkward when the MTUs are originally installed or have to be replaced.
One approach to this problem is shown in U.S. patent application Ser. No. 07/843,136, filed Feb. 28, 1992. There, each MTU is mounted in slots in the terminal housing beneath the customer bridges. Each MTU is coupled to a mother board perpendicularly thereto and coupled to an RJ11 jack by a pair of electrical connectors of the MTU board.
It is desirable to provide an alternative approach to mounting an MTU or other component in a network interface unit. It is particularly desirable to be able to mount the component from the front of the network interface unit.